If you're looking for examples of how fear or anger in real life would help some one.
You can't use a football game as an example of "anger" we're talking about Hate, Rage, Seething and Loathing the want for something to end as slowly and painfully as possible, This can insight blood lusts which can cause people to sort of black out and forget large swaths of what occurred, this would be the caveat of what i'd imagine the Jedi strive for which is "Wu Wei." Acting without acting, Performing such a fluid and precise motion that you feel as though you didn't perform it your self. This is something real people do all the time, it's most common in sports and you say it's harder to achieve when you're angry because when you're angry you're distracted. When you hate, you have only one thing on your mind.
People who have had boulders fall on them find miraculous strength because they are afraid of death, this is the most primal, instinctual, basic of emotions. The unadulterated want to live. Fear is taught to Sith Acolytes because they are constantly shadowed by a master who could take their life at any minute. They live in a culture where murder, power grabs, and mutiny is common place. Paranoia is what controls people, but when your life is in danger and you are unsure if you will live moment to moment the amount of stress that would be flooding your system is unimaginable. When a being is scared for its life, it will lash out and sacrifice part of it self to continue living in most cases.
The Sith you idolize in the movies are fat cats where the only thing they have nothing to fear, and remember it all starts with fear.